PURPOSE: A rectangular shear cotter is provided to improve economical efficiency and productivity when manufacturing a roller and to promote bending and shearing stress of a hollow core slab. CONSTITUTION: The rectangular shear cotter(4) is produced by making a roller having a rectangular shear cotter pass through the upper part of a hollow core slab(2) which is manufactured by making a hollow core slab manufacturing frame pass through a bed. Wherein the roller having a rectangular shear cotter is installed to the backside of a hollow core slab manufacturing frame.
